1. Field of the Invention
The present invention relates to an improved compact generator, a light-emitting wheel having the same, and a manufacturing method of the light-emitting wheel, and more particularly, to an improved compact generator, a light-emitting wheel having the same, and a method of manufacturing the light-emitting wheel, exhibiting compatibility without being limited to the diameter with respect to the existing axle so that electromagnetic induction is more efficiently performed compared to a conventional generator, mechanical stability and movability of a wheel structure which are very important points in a wheel are not lowered, even if a generator is included, as the structure thereof becomes simplified, and simultaneously, the efficiency in manufacturing the light-emitting wheel, that is, mass production thereof, is increased, and a user can easily replace the wheel.
2. Description of the Related Art
Various types of conventional technologies relating to a roller skate wheel adopting a light-emitting mechanism have been suggested.
U.S. Pat. No. 4,298,910 discloses a roller skate wheel with a self-contained generator in which a permanent magnet is secured to an inner stationary body and electromagnetic induction coils are provided at an outer rotatable body. When the outer rotatable body rotates via bearings, current is induced by electromagnetic induction generated between the electromagnetic induction coils in the outer rotatable body and the permanent magnet in the inner stationary body so that light-emitting diodes installed in the outer rotatable body are energized.
However, in the structure of the above roller stake wheel, the electromagnetic induction mechanism is not compact. Also, as there is no armature arm, the direction of the magnetic field of the permanent magnet is not electromagnetically coupled to the direction of electromagnetic induction coils so that electromagnetic induction is not smoothly generated. Further, as the rotating armature coil is installed outside a hub, the structure of the wheel becomes substantially weakened and the permanent magnet is easily damaged by the impacts received while the wheel actually runs.
Furthermore, as the processes of installing the light-emitting diodes in the wheel and connecting the armature coil and the light-emitting diodes are manually performed, mass production of the roller skate wheel is difficult.
Meanwhile, as another prior art, U.S. Pat. No. 5,580,093 discloses that a light-emitting mechanism is provided at the wheel of an in-line roller skate. However, the electromagnetic induction mechanism is not compact and, although there is an armature arm, as the direction of a permanent magnet and the direction of an armature coil form a parallel structure, not a perpendicular structure, the length of an armature arm is increased so that electromagnetic induction becomes weak. Also, as there is no apparatus for protecting the permanent magnet from being damaged by the impacts generated during actual running, a rare-earth based permanent magnet such as neodymium (Nd) or samarium (Sm) of Lanthanides in the periodic table of the elements, which has a strong magnetic force but weak against impacts, is not used as it is easily broken, and a ferrite based permanent magnet which exhibits a relatively strong impact resistance is used so that the efficiency of the generator is lowered and the size and weight of the generator increases. Further, as the connection between the armature coil and the light emitting devices is not easy, there is a problem in mass production.
Also, in U.S. Pat. No. 5,810,450 as another prior art, although a structure of an armature coil rotating around a permanent magnet is adopted, as there is no damage protection device for the permanent magnet from impact occurring while running as in the above-described prior art, a rare-earth based permanent magnet such as neodymium (Nd) or samarium (Sm) of Lanthanides in the periodic table of the elements is easily broken during use. Accordingly, a ferrite based permanent magnet exhibiting a relatively strong impact resistance is used so that the efficiency of the generator is lowered, the size and weight of the generator increases, and alos brightness in light emission is lowered and mechanical stability and movability of a wheel itself are lowered. Further, as the connection between the armature coil and the light emitting devices is not easy, there is a problem in mass production. Also, as a wheel hub maintaining the inside of the wheel cannot be injection-molded in a body and two half wheel hubs are assembled using an adhesive, costs for assembly increase much while durability of the wheel is lowered.
To solve the above problems, it is an objective of the present invention to provide an improved compact generator having a super compact structure so that electromagnetic induction is efficiently performed, durability is improved, and mass production is possible.
It is another objective of the present invention to provide a light-emitting wheel having the improved compact generator having a super compact structure so that electromagnetic induction is smoothly performed, durability is improved, and mass production is possible.
It is another objective of the present invention to provide a light-emitting wheel having the improved compact generator in which the structure of the permanent magnet assembly and the armature coil assembly forming the generator is improved so that mechanical endurance, stability and movability, and commercial economic value and productivity are improved.
It is another objective of the present invention to provide a light-emitting wheel having the improved compact generator in which a light-emitting device installation circuit board is used for facilitating installation of the light-emitting devices and other circuit devices needed for efficient light emission, and also the connection to the armature coil is made easy to improve mass production.
It is another objective of the present invention to provide a method of manufacturing a light-emitting wheel by which, when a wheel hub incorporated with an armature coil assembly having the structure for facilitating electromagnetic induction is injection-molded, a lead wire can be extended to an additional light-emitting device installation circuit board without damage, and a process of transmitting the generated current to the light-emitting device using the additional light-emitting device installation circuit board is simplified, thus improving mass production.
Accordingly, to achieve the first objective, there is provided an improved generator for generating electricity according to the rotation of a wheel, the generator, which comprises a ring type permanent magnet assembly encompassing a buffer fixedly encompassing a bearing spacer installed on a stationary wheel axle, in which a permanent magnet is fixed and the poles of the magnet are alternately arranged in a circumferential direction, a rotatable ring type armature coil assembly which rotates while coaxially encompassing the permanent magnet assembly in a non-contact state so that electromagnetic induction is generated in an armature coil by an armature arm alternately magnetized by the poles alternately arranged on the permanent magnet assembly, and where a lead wire protrudes and is guided to be connected to the outside, bearings, installed at both sides of the armature coil assembly and supported by the wheel axle and the bearing spacer, including a stationary bearing portion which is not allowed to rotate during rotation of the armature coil assembly and a rotary bearing portion which rotates when the armature coil assembly rotates, and a hub assembly in which the permanent magnet assembly is fixedly inserted around the bearing spacer on the wheel axle and the armature coil assembly fixedly molded together when a hub is injection-molded is supported by the bearings, forming a rotatable body.
To achieve the second and third objectives, there is provided a light-emitting wheel having an electromagnetic induction mechanism for operating a light-emitting device during rotation of a wheel, which comprises a generator assembly having a ring type permanent magnet assembly fixed by a buffer fixed to a bearing spacer, the poles of the magnet are alternately arranged in a radial direction, a ring type armature coil assembly rotating while encompassing the permanent magnet assembly fixed to the bearing spacer in a non-contact state so that electromagnetic induction is generated in an armature coil by an armature arm alternately magnetized by the poles alternately arranged on the permanent magnet assembly, where a lead wire protrudes and is guided to be connected to the outside, bearings coupled to the buffer and the bearing spacer supported by an inner race of the bearing which is a stationary bearing portion to prevent the permanent magnet assembly from rotating when the armature coil assembly rotates, a light-emitting device installation circuit board on which one or more light-emitting devices are installed and simultaneously a circuit for allowing the light-emitting devices to efficiently emit light as necessary to which a lead wire coil from the armature coil assembly integrally formed with the wheel hub is connected, and a wheel hub assembly having an inner frame portion having a plurality of frames and supported by an outer race of the bearings in which the generator assembly is inserted, and an outer frame portion extended from the inner frame portion and substantially included in the wheel of a transparent material along with the light-emitting device installation circuit board, in which the inner frame and the outer frame are fixedly molded together with the armature coil assembly during injection-molding the wheel hub.
It is preferable in the present invention that said permanent magnet and buffer comprises a buffer, supported at an inner race of the bearings, having an inner diameter so that wheel axles of various diameters can be smoothly inserted to secure compatibility with respect to the wheel axles of various diameters, fixed to said bearing spacer partially having a step inserted into a part of the inner hole (a bearing inner diameter portion) through which the axle passes in the bearings, and having a plurality of buffer wings protruding around the circumference thereof for absorbing impacts applied to said permanent magnet during running of said wheel, and a ring type multi-pole permanent magnet fixed to the buffer in which the poles of the magnet are alternately arranged in a radial direction.
It is preferable in the present invention that the ring type armature coil assembly comprises an armature coil spool onto which the armature coil is wound, a first half cover in which the armature arms are disposed to protrude at predetermined intervals perpendicular to a surface of the cover, and a second half cover, encompassing the armature coil spool by being coupled to the upper portion of the first half cover, in which the armature arms are disposed to protrude to alternate with the armature arms of the first half cover, perpendicular to a surface of the cover, in which, during rotation, polarity induced to the armature arm of the first half cover and that induced to the armature arm of the second half cover by the alternately arranged poles of the permanent magnet are changed alternately so that current is generated in the armature coil.
It is preferable in the present invention that the armature coil spool of the armature coil assembly comprises a protruding guide pipe having a groove for guiding an armature coil lead wire to the outside through a hole formed at the upper portion of the first half cover, and a hub and an armature coil assembly are integrally injection-molded, so that the armature coil lead wire can be prevented from being damaged when the armature coil and the hub are injection-molded and the armature coil lead wire can be easily connected to the light-emitting device.
It is preferable in the present invention that the light-emitting device installation circuit board is formed of a thin circular, semicircular, quadrantal circular, or smaller conductive plate and a plurality of light-emitting devices and electronic circuit elements as necessary are installed at predetermined intervals along the circumference thereof, so that all light-emitting devices are connected by connecting the armature coil lead wire of the armature coil lead wire to only a single light-emitting device.
It is preferable in the present invention that the light-emitting device is a light-emitting diode or a bulb LED chip mounted on a surface of the conductive plate, and that the light-emitting wheel further comprises a transparent bulb protection cap if the light-emitting diode is of a bulb type.
The light-emitting wheel according to the present invention has a flexible structure coupled with the frame of a roller skate by a coupling bolt of a rod-shaped structure having a diameter and length suitable for roller skates, in-line roller skates, skate boards or bound skates so that axles of different lengths and diameters, which are made by various manufactures of skates, can fit well.
To achieve the fourth objective, there is provided a method of manufacturing a light-emitting wheel having a light-emitting mechanism in which power is self-generated by rotation of wheels, which comprises the steps of forming a permanent magnet assembly by encompassing a buffer with a permanent magnet, the buffer having buffer wings for preventing impact to the permanent magnet, forming an armature coil assembly, in which armature arms alternately protrude from covers encompassing a spool where an armature coil is installed, having a protruding guide pipe for guiding the armature coil to the outside, injection-molding a hub in which the armature coil assembly is molded by inserting the armature coil assembly when a wheel hub is injection molded installing a thin conductive plate on which light-emitting devices are installed at an outer frame of the wheel hub, connecting a lead wire coil from the armature coil assembly to any one of the light-emitting devices, forming a urethane mold to be fixed to the outer frame of the wheel hub, forming a wheel by inserting the wheel hub in a mold in which a urethane tire is injection-manufactured and fixed to the outer frame of the wheel hub by injecting thermosetting transparent liquid polyurethane resin therein, separating the mold when the polyurethane is cured, assembling a wheel by fitting a bearing and a bushing in the bearing spacer protruding through one side of the wheel hub, and completing the assembly of a wheel by fitting a bearing and a bushing in the bearing spacer protruding with the permanent magnet assembly in the wheel through the other side of the wheel hub.